1. Field of the Invention
The present invention relates to a centrifugal blower. In particular, the present invention relates to a centrifugal blower with a simplified structure to allow simple assembly.
2. Description of Related Art
FIG. 1 of the drawings illustrates a conventional centrifugal blower comprising a housing 1, a cover 2, and an impeller 3. The housing 1 includes a compartment 11 and a radial air outlet 12. The cover 2 is mounted on the housing 1 and includes an axial air inlet 21. The impeller 3 is rotatably mounted in the compartment 11 of the housing 1 and includes a hub 31, a supporting plate 32 extending outward from the hub 31, and a plurality of blades 33 fixed on the supporting plate 32. In operation, the blades 33 suck axial airflow via the axial air inlet 21 of the cover 2 when the impeller 3 turns. Then, the axial airflow is driven by the blades 33 to exit the housing 1 via the radial air outlet 12 for dissipating an object (such as a fin).
In assembly, the impeller 3 is firstly mounted in the compartment 11 of the housing 1. Then, the housing 1 and the cover 2 are engaged together by a suitable method (such as by engaging members, screwing, welding, or bonding). The assembling procedure is troublesome. Further, both of the housing 1 and the cover 2 have a complicated structure for engaging with each other, rendering it difficult to cut the cost for manufacturing the molds for the housing 1 and the cover 2 and to minimization of the centrifugal blower. Further, the cover 2 limits the axial height of the blades 33 of the impeller 3. Further, since the lower edge of the axial air inlet 21 of the cover 2 is stationary while the upper edges of the blades 33 are rotating, turbulent and noise occur easily in an area therebetween. Further, the air in the compartment 11, when accumulated to a certain amount, leaks to the environment via the axial air inlet 21, failing to provide the expected pressure-boosting effect.